Tire inspection apparatus



Feb. 1942- G. P. BOSOMWORTH 93 TIRE INSPECTION APPARATUS Filed July 25, 1939 '6 Sheets-Sheet 1 INVENTOR ATTORNEYS 1942- G. P. BosoMwoRTH TIRE INSPECTION APPARATUS Filed July 25, 1939 I 6 Sheets-Sheet 2 INVENTO R 072221222229;

ATTORN EYS Fe. 10, 1942. G. BOSOMWORTH' 2,272,393

TIRE INSPECTION APPARATUS Filed July 25, 1939 6 Sheets-Sheet 5 INVENTOR ATTORNEYS 1942. G. P. BOSOMWQRTH TIRE INSPECTION APPARA'DUS Filed July 25, 1939 6 Sheets-Sheet 4 s Y E m T T A Feb. 10, 1942.

G. P. BOS OMWORTH TIRE INSPECTION APPARATUS Filed July 25, 2939 v 6 Sheets-Sheet 5 INVENTOR ATTORNEYS Feb. 10, cs. 1 BosoMwoRTH 2,272,893

- TIRE INSPECTION APPARATUS Filed July 25-, 1959 6 Sheets Sheet 6 INVENTOR BY I " ATTIORNEYSI 1 Patented Feb. 10, 1 942 TIRE INSPECTION APPARATUS George P. Bosoniworth, Akron, Ohio, assignor to The Firestone Tire & Rubber Company, Akron, Ohio, a corporation of Ohio Application July 25, 1939, Serial No. 286,387

7 2 Claims. This invention relates to apparatus for inspecting vehicle tires, and more especially it relates to apparatus for inspecting the internal ,structur of vehicle tires to determine the presence offoreign matter, such as tacks, nails or other metal,

or stones or the like that may have penetrated the body thereof, or to discover breaks, injuries or other structural defects in the fabric carcass of pneumatic tire casings.

More particularly the invention'relates to ap-'- paratus employing X-rays as a means for producing a visual image of the internal structure there is shown a mobile apparatus comprising a platform l4 that is mounted upon a plurality of swivelled wheels or casters l5, I so as to be capable of being moved to desired positions, said platform having acentral rectangular opening 2| in its surface at the front thereof. For holding the platform stationary while tire-inspections are being made, a pair of foot-like pads I6,

I I6 are provided, which pads are normally-held of a tire, and in some of its aspects is an improvement upon the subject matter of U. S. Patent No.

1,617,758, issued February 15, 1927, to H. C. Heynemann.

The chief objects of the invention are to pro-* provide adequate protection to operators who.

are making the inspection; and to provide improved means for marking a tire .to indicate the location of foreign matter or other abnormal conditions. Other objects will be manifest as the specification proceeds.

0f the accompanying drawings:

Figure 1 is a front elevation of apparatus constituting one embodiment of the invention; 4

Figure 2 is a section on the line 2-2 of Figure 4;

Figure 3 is a plan view of the apparatus shown in Figure 1;

Figure 4 is a side elevation thereof as viewed from the left of Figure 1;

Figure 5 is a plan view of another embodiment of the invention taken on the line 55 of Figure 6; Y

Figure 6 is a side elevation thereof, and a motor vehicle mounted-thereon;

in position above the fioor by a tension spring [1, Figure 4, common to the two pads. A pedaloperated cam member I8 is provided for forcing the pads l6 downwardly into engagement with the floor'to hold the platform l4 stationary in desired position. The arrangement is such that the inspection apparatus readily may be wheeled into proper position with relation to a tire on a motor vehicle after the latter is elevated to the desired position by means of a jackor similar apparatus. Such a tire is shown at 22, and a fragmentary portion of the vehicle is shown at 23, The tire may be rotated by means of a suitable stick or wand of sufiicient length to enable the operator to remain at a safe distance from the X-rays while turning the tire.

Mounted upon the top'of platform 14, at therear thereof, is a housing 25 within which is type, th focal point of the X-ray tube being in.-

' dicated at 21, Figure 4. There is a restricted Figure 7 is a plan view of still another embcd iment of the invention;

Figure 8 is a side elevation thereof; Figure 9 is a sectionon the line 99 of. Figure 7 Figure 10 is a front elevation of apparatus con-' stitutmg another embodiment of the invention;

opening at 28 in the front of box 26 and a somewhat larger opening 29, Figure 4, in the front of housing 25, said openings enabling the X-rays from the tube to impinge upon the tire 22. To assist in cooling the X-ray tube, an electrically driven blower fan 30 is mounted within the housing 25 in position to direct a. current of air against the box 26, the housing 25 being formed with louvers 3i to admit air thereto. Also mounted within the housing 25, beneath the fan in the housing 25, at the opposite end thereof from the stabilizer I9, is a distributor panel 20 A upon which is mounted other accessories for the Figure 11 is asection'thereof similar to Figure 2 of a previously described embodiment;

Figure 12 is a plan view of the apparatus shownin Figure 10; and I V Figure 13 is a side elevation thereof as viewed from the left of Figure 10.

vReferring to Figures 1 to 4 of the drawings, 5:;

operation of the X-ray tube, such as fuses,'mil1i"- ammeter and rheostat, and switches, such accessories being standard equipment and not requiringfdetail illustration or description herein.

As is best shown in Figure 4, the foeal point of *the X-ray tube is not exactly opposite the side of the tire 22 but at asomewhat elevated'po sition, and the opening 28 in-the box 25 is so able brackets 31, 31 secured to the arranged that most of the X-rays are downwardly inclined or tilted from said focal point, the arrangement being such that the rays pass angularly through the tread portion of the tire. n the opposite side of the tire 22 rom the X-ray mechanism described is a relatively large protective apron or plate 32 of lead-coated steel, said. plate being mounted upon the front margin of the platform l4. At its lower margin the plate 32 is cut away to receive a fluoroscopic screen 33 that is mounted in a suitable frame 34, said screen being so positioned as to receive the shadow or image of the tire produced by the X-rays from the X-ray tube in box 26. Secured to th front of plate 32 is a visor 35 of conoidal shape, the large end of the visor circumscribing the screen 33, the small end of the visor comprising a suitable aperture through which the image on the screen may be viewed. Secured to the back of plate 32 is a reservoir 44 for oil that is utilized to cool the X-ray tube, there being a pipe line 45 from said reservoir to the X- 1 ray mechanism.

As a further protection to the operator or mounted lead-coated plates 36, 36 are Provided, which plates are disposed in the plane of the tire, between the housing and the plate 32.- Said plates are pivoted at their lower ends upon suitplatform l4, and when in substantially upright position they are disposed adjacent the tire 22, fore and aft thereof. The plates 36 are connected to each other by a tension spring 38 that normally urges them toward each other when said spring is over center with relation to the pivot points of the plates in brackets 31, the movement of the plates toward each other being arrested by engagement of the plate-margins with the top of platform H, at the pivoted end of the plates, as is best shown in Figure 2. The pivotal mounting of the plates to facilitate the positioning of the apparatus in operative relation to a tire on a vehicle, and when in downwardly tilted position the plates serve to open respective cam-operated cut-out switches I00, I00 arranged in series in the electrical circult of the X-ray mechanism, the arrangement being such as to prevent energising of the X-ray tube, except when the plates 36 are in elevated position.

The apparatus is provided with a manually operated marking device by which the location of hidden defects, as revealed by the X-rays, may be indicated'on the tire. Said marking device comprises an arm 40 that is disposed below the opening 2| in the platform, and is supported at one end upon a suitably journaled, axially and angularly movable rod 4|, the latter being disposed below the surface of the platform at one side of opening 2| and provided at its forward end with an operating lever 42 by which it may be moved.

axially or rocked angularly. The arm 40 extends laterally from the rod 4|, its free end being disposed substantially in the same vertical plane as the axis of the tire 22, and provided with a suitable marking substance 43 such as chalk 0r crayon. In Figure 1 the arm 40 is shown in two alternative angular positions, and in Figure 3 is shown in two alternative lateral positions.

In the operation of the apparatus described, a

source of electricity (not shown) in the usual manner, the X-ray emanations passing through the body ofthe tire obliquely and projecting the shadow or image thereof on the fluoroscopic screen 33. Thus an inspector gazing into the visor 35 at the small end thereof readily can detect the presence of any foreign substances within the structure of the tire. The tire 22 is caused Y to rotate slowly by an assistant who uses a nonmetallic rod for th purpose and stands at a position out of range of the X-ray emanations. When a defect in the tire is discovered, the inspector marks the location thereof by means of the crayon 43-which he manipulates by means of the lever 42.

Ordinarily a single tire inspection can be made in from 1 to 2 minutes. The X-ray tube should not remain energised for intervals of longer than two minutes, and should be allowedto cool for at least etwo minutes before again being energised. The two minute cooling interval may be advantageously utilized for moving the apparatus into operative position with relation to another tire on the vehicle. I

The apparatus is so constructed as not to require a tire to be removed from a vehicledn order than an X-ray inspection may be made,"thereby conserving time and labor. The apparatus is mobile so as to be available for use at any place where electric power is available, it is adequately shielded to provide protection to operators, and

- it achieves the other advantages set out in the 36 enables them to be tilted downwardly so as vehicle having thereon pneumatic tires to be inspected is elevated at one end by means of a jack or the like, and. the inspection apparatus is moved under one of the tires thereof to a position 16 foregoing statement of objects. r

The embodiment of the invention shown'in Figures 5 and 6 is known as the drive-on type, which differs from that previously described in that the vehicle does not require to be lifted from the ground while its tires are being inspected. The apparatus requires the use of a pit 46 which is-similar to pits used for greasing purposes, and may, in fact, also be used for that purpose. Channel-like trackways 41, 41 extend along each side of the pit at ground level for receiving the tires of a vehicle to guide the latter accurately to position over the pit. In Figure 6 is shown a vehicle 48 in position for inspection of its tires. When so positioned the front tires 49 of the vehicle rest upon respective pairs of grooved rollers orv spools 50, 50, which spools are mounted in gaps in the respectivetrackways 41 on axes disposed transversely of said trackways. The spools 5|] on one side of pit 46 are in axial alignment with the spools on the. opposite side thereof, and two of said aligned spools are mounted upon a common rotatable shaft 5| that spans the pit. The shaft 5| is rotated by means of a motor 62 that is mounted in the pit and connected to said shaft by a transmission belt or chain 53, the arrangement being such that the one spool 50 of each pair of spools may be driven slowly by means of the motor 52 and thereby to effect the rotation of the two front wheels and tires 49 of the vehicle 48. In like manner the rear wheels 55 of the vehicle are adapted to rest upon respective pairs of spools or rollers 56, 56, the rear spools of the respective pairs of spools being mounted upon a common shaft 51 that spans the pit and is driven by a motor 58 to which it is connected by means of a transmission belt or chain 59. The

' screens (not shown).

pairs of spools 56 havelimited adjustability longitudinally of the trackways 41 to adapt the 'apparatus to vehicles of. different wheel base lengths.

Mounted within the pit 46 upon upright posts or standards 6|, 6| is an endless trackway 62 of elliptical shape; Mounted upon said trackway 62 is a wheeled carriage 63, and mounted upon the latter is a lead-lined box 64- that encloses an X-ray tube (not shown) that is similar to that employed in the previously described embodiment of the invention. The carriage 63 is movable along the traekway 62 so as to position the X-ray tube behind the respective tires of the vehicle 48, the carriage being motor driven or cable propelled as desired. 1

Over the pit 46 and trackways 41 is a housing structure 66 of sufiicient size to enclose the vehicle 48, said housing structure having doors at one or both ends thereof to provide ingress and egress for the vehicle. The housing structure 66 is lined with lead to prevent the radiation of X-rays therefrom. The respective sides of the housing 66 are formed with embrasures 61, 61 located opposite the tires of the vehicle when the latter is supported upon the spools 58 and 56, and mounted in said embrasures are respective screen frames 68 that support the usual fluoroscopic The arrangement is such that when the X-ray tube is positioned behind a tire and energised, the shadow or image of the tire will be projected onto a fluoroscopic screen. For the better viewing of such an image, a portable visor 69 is provided, which visor may be placed in front of the respective fluoroscopic screens alternatively as the carriage 63 is moved to operative positions behind the various tires of the vehicle The visor 69 is essentially of the same construction as the visor 35 previously described so that a detail description thereof is not required.

This embodiment of the invention accomplishes the same purpose as that previously described, but is a more or less permanent installation and utilizes a greasing pit with which most garages and service stations already are provided.

The embodiment of the invention shown in Figures 7 to 9 also is a permanent installation designed for use in garages and the like. It comprises a pit 12 that is suitably positioned in the middle of a driveway for motor vehicles. Mounted in said pit is a hydraulic lift 13 carrying a rotatable circular turntable-14 thereon,

while the latter is on a vehicle, such as indicated. at 84. One of the spools 8| in each pit metal plates 81, 81 are hingedly' mounted at each side of each pit 89, said plates being positionable over the pit to conceal and protect the con;- tents thereof, and being alternatively positionable in substantially upright position, at fore,

and aft positions with relation to a tire 83 being inspected, as shown in Figure 9, to constitute shields against X-ray emanations.

Respective parallel protective walls 90, 90 of lead-coated material are positioned on opposite sides of the driveway and span the respective pits 88 laterally of the spools 8|. The walls 90 are indented above each of said pits, and respective fluoroscopic screens 9| are mounted in said pits extending from the bottom thereof to the top of the indentures in the wall 90. Each screen 9| is so positioned as to receive the shadow or image of a tire 83 projected thereon by the X-rays from the box 15, when the latter is positioned adjacent that particular screen. Vertically slidable panels 92 may be provided for protecting the respective screens 9| when the latter are not in use. outwardly of the walls 99 the pits 80 slope upwardly to ground level, said sloped portions of the pits accommodating respective visors 93 of conoidal shape, that are secured at their larger ends to the outer face of the walls 90. The small end of'each'visor is open to enable the image on the screen 9| to be viewed therethrough.

In this embodiment-of the invention a vehicle is driven into operative position with relation to the apparatus, the front tires of the vehicle resting upon-the spools 8|. The X-ray tube'is then energised and the tire adjacent said tube is inspected while the tire is slowly rotated by means of motor 85. Thereafter the turntable ,'is rotated through 180 and a similar inspection and mounted upon the top of the latter is a leadlined box 15 in which is mounted an X-ray tube (not shown), the focal point of said tube being indicated at 16. The box 15 has arestricted opening 11 in the outwardly facing wall thereof to enable the passage of X-rays therethrough, the opening being so arranged that the X-ray beam is directed obliquely downwardly. The turntable 14 also carries a cover plate 18 that extends overthe box 15, the arrangement being such that when the hydraulic lift 13 is in lowered position the cover plate 18 is flush with the floor and so conceals and protects the X-ray apparatus on the turntable.

At diametrically opposite points with relation to the pit 12 are shallower pits 80,89, and suitably mounted in each pit are two parallel, spacedapart grooved rollers or spools 8|, 8 The spools 8| are located in the top of pits 80, substantially flush with the ground level, the arrangement being such that each pair of spools is adapted to receive and support a vehicle tire 83' made of the other front tire. vehicle is driven forwardly until its rear tires are properly positioned for inspection purposes, and the previously described inspection operations repeated. This completes the cycle of operations. p

The embodiment of the invention shown in Figures 10 to 13 of the drawings is essentially similar to that shown in Figures 1 to 4, but in addition thereto includes means for supporting a wheel tire to be inspected in determinate position within the apparatus. Said means comprises a pair of laterally spaced apart grooved spools 94, 94 that are arranged on parallel horizontal axes and journaled in suitable bearing brackets 95, 95 rising from the top of platform |4a, at opposite sides of the opening 2|a in the latter. The shaft of one of the spools 94 extends forwardly through the protective plate 32a,

and has its end portion provided with a hand crank-96 by which the spool 94 may be rotated. Rotation of a spool 94 will effect rotation of the 91 resting thereon for inspection, and the hand crank 96 is conveniently positioned to be rotated by an inspector while gazing into the visor 35a. The spools. 94 properly position the tire so that the downwardly inclined X-ray beam" projects the shadow of the tire onto the fluorescent screen 330, and the latter is of suflicient Thereafter the l clearly revealed upon the screen 33a, thus makin: possible more eflicient inspection.

Other modification may be resorted to without departing-from the spirit of the invention tion of a vehicle tire therebetween, a mobile platform supporting said x-ray tube and screen whereby the same may be moved into operative position with relation to a-tire on a' vehicle, and pivotally mounted protective plates swinzsble to operative positions fore and aft of the tire to aflord protection against X-ray emanations, and

or the scope thereof as deiined by the appended claims.

What is claimed is:

1. In tire inspection apparatus, the combine.- tion of an X-ray tube and a fluoroscopic screen spaced apart from each other to admit a. pormovable to inoperative positions enabling them to pass under the tire when the platform is moved relatively of the tire.

2. Acombination as defined in claim 1 ineluding cut-out switches in the X-ray circuit and operatively associated with the respective protective plates, said switches being arranged in series and preventing operation or the X-rays when either plate is in inoperative position.

GEORGE P. BOSOMWORTH. 

